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Using Network Models To Predict Steelhead Abundance, Middle Fork John Day, Or, Monica R. Blanchard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is important in the management of threatened and endangered species to have informed population estimates. Population estimates are used to gage whether or not recovery goals are being met. When assessing Pacific salmonids this assessment involves sampling a small subset of the population and then scaling up to estimate larger populations units. This is complicated by the fact that fish populations are not evenly distributed along river systems but respond to fluctuating physical and biological stream properties. We used rapid assessment survey methods and the River Styles classification to explore fish-habitat relationships. River Styles is a classification system that …

Relationships Between Water Developments And Select Mammals On The U.S. Army Dugway Proving Ground, Utah, Bryan M. Kluever

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water is essential to life. Three general forms of water exist: pre-formed water that is available in food, metabolic water that is created as a byproduct of life processes (e.g., metabolism of fat or breakdown of carbohydrates), and free water (i.e., water available for drinking). As humans settle arid environments, the addition of man-made free water sources (e.g., sewage ponds, catchment ponds) often occurs. In addition, a tool commonly used to increase the abundance or distribution of wildlife species in desert environments is the addition of water sources, usually specifically designed to benefit game species like bighorn sheep (Ovis …

Pregenomic And Genomic Effects Of 24,25-Dihydroxyvitamin D3, Yang Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the United States, the major dietary source of protein is poultry meat, particularly chicken. Phosphorus absorption in chickens is a critical problem in poultry production. It therefore is important to understand the cellular and molecular regulation of phosphorous absorption in intestine to increase efficiency of the process. This would provide the benefits of reducing feed costs and reducing phosphorous excretion, thereby contributing to the sustainability of agriculture in the United States. Therefore, the focus of this thesis is determining the effect of vitamin D metabolites involved in phosphate homeostasis using the chicken as a model.

Winter Ecology Of Common Ravens In Southern Wyoming And The Effects Of Raven Removal On Greater Sage-Grouse Populations, Luke W. Peebles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Common raven (Corvus corax; hereafter raven) populations have been increasing rapidly in the western United States, and these ravens cause damage to livestock, human health and safety, and wildlife species including greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse). The goals of my research were to gain a better understanding of the winter ecology of ravens, to see how raven populations were impacted by intensive removal during the winter, and to determine if raven removal aids sage-grouse populations. I found that ravens captured at landfills used these landfills sporadically for foraging, and these ravens regularly used bridges and …

Modeling Seed Dispersal And Population Migration Given A Distribution Of Seed Handling Times And Variable Dispersal Motility: Case Study For Pinyon And Juniper In Utah, Ram C. Neupane

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spread of fruiting tree species is strongly determined by the behavior and range of fruit-eating animals, particularly birds. Birds either consume and digest seeds or carry and cache them at some distance from the source tree. These carried and settled seeds provide some form of distribution which generates tree spread to the new location. Firstly, we modal seed dispersal by birds and introduce it in a dispersal model to estimate seed distribution. Using this distribution, we create a population model to estimate the speed at which juniper and pinyon forest boundaries move.

Secondly, we introduce a fact that bird …

Factors Contributing To The Conservation Of Phacelia Submutica (Boraginaceae), A Threatened Species In Western Colorado: Reproductive Biology And Seed Ecology, Alicia M. Langton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Conservation and recovery plans for rare species require biological and ecological information to discern how they may be susceptible to human disturbances. Phacelia submutica is a threatened annual species in western Colorado. Human activities including energy development, recreation, and livestock grazing are occurring within the species’ range. To provide conservation practitioners with a scientific basis for management, this research aimed to elucidate elements of the species’ ecology. Chapter 2 describes the reproductive biology of P. submutica. Potential insect pollinators were not observed during two years of observations. Floral traits and development ensure self-pollination and reduce the likelihood that insects …

The Baker Cave Bison Remains: Bison Diminution And Late Holocene Subsistence On The Snake River Plain, Southern Idaho, Ryan P. Breslawski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis investigates that paleoecology of southern Idaho bison and their role in prehistoric subsistence with two articles. The first article investigates the trajectory of bison diminution in southern Idaho with bison morphometrics from Baker Cave, a late Holocene archaeological site. Results indicate that local bison followed a diminution trend mirroring the diminution trend documented on the Great Plains. This suggests that similar bottom up ecosystem controls acted on bison in both the Great Plains and in southern Idaho through the Holocene.

The second article examines the role of bison in seasonal subsistence strategies. I hypothesize that winter fat scarcity …

Assessing Changes In Waterfowl Population And Community Dynamics, Beth E. Ross

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studying long-term ecological studies can help ecologists understand what causes populations and communities of wildlife to change. Understanding these causes can help guide conservation efforts. Additionally, results from long-term datasets allow ecologists to predict how populations may shift with global change. Ecologists can then determine necessary management action to maintain sustainable populations in the future. However, there can be a large amount of “noise” in a long-term dataset. If ecologists fail to account for this noise, they may make incorrect management decisions. For example, samples taken in two nearby locations will likely be more similar than samples taken from two …

An Evaluation Of The Food Web Dynamics And Predator Prey Interactions In Scofield Reservoir, Lisa K. Winters

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reservoirs are artificial, dynamic, and highly manipulated systems, where the appearance of either intentionally or unintentionally introduced species may disrupt interactions within an already complex food web. In some situations, a top predator fish may be stocked as a biological control agent, if these fish-eating predators monopolize on the nuisance and unwelcome prey. Scofield Reservoir, Utah has historically been an extremely popular blue-ribbon fishery. However, a recent decrease in rainbow trout catch and increase in the minnow, Utah chub, have made it difficult to find a balance between providing the public with a trophy sport fishery and maintaining an ecologically …

Systematics And Behavioral Evolution Of Spider Wasps (Hymenoptera: Pompilidae), Cecilia Waichert Monteiro

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider wasps form a diverse and widespread group of stinging wasps. Although all Pompilidae have similar life history characteristics, there is considerable variation in nesting behavior modes and, thus, this family could be useful for learning about the evolution of nesting behavior in insects. The nesting behavior of many species is well known, the family is monophyletic and easily recognized, and certain species have some degree of pre-sociality, i.e., communal nesting. All these factors suggest that the Pompilidae are an important model group for understanding mechanisms and patterns of behavioral evolution.

Pompilidae, however, are rarely studied and their research potential …

Macroinvertebrate-Driven Nutrient Recycling In Four Large Rivers, Matt A. Schroer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The cycling of nutrients is a fundamental process in streams and rivers, and scientists are increasingly recognizing the importance of animal communities to nutrient dynamics in these ecosystems. Despite growing evidence that animal excretion (i.e. urine) can supply limiting nutrients to primary producers in small streams, the importance of excretion is uncertain in large rivers. Accordingly, I used three estimation approaches based on past and new excretion rate data to determine nitrogen (N) and phosphorus (P) excretion inputs from insect communities in four large rivers (discharge > 10 cubic meters per second) in North America, and I compared these rates to …

Stem Development, Seeding Rate, And Establishment Of Birdsfoot Trefoil (Lotus Corniculatus) For Organic, Grazing-Based Dairies, Sara Hunt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Birdsfoot trefoil (BFT, Lotus corniculatus L.) is a non-bloating, productive forage legume well suited to grazing-based ruminant production. This thesis presents three studies conducted in the Mountain West applicable to organic management and cultivation of BFT. The first is an analysis of lignification in BFT stems that supports recommendations to harvest BFT at approximately 6 weeks of regrowth, or early bloom. Lignification decreases digestibility and is correlated with high shear force required for grazing animals to break BFT stems. The process of stem lignification was observed by harvesting increasingly mature stems; cutting thin sections of the sixth stem internode, which …

Presence And Function Of Tetrodotoxin In Terrestrial Vertebrates And Invertebrates, Amber N. Stokes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tetrodotoxin (TTX) is a potent neurotoxin found in a variety of species. This toxin has long been of concern to human health as it is found in puffer fish, which are a delicacy in Japan. Since the distribution of this toxin is so great, there are many questions regarding the evolution and ecology of organisms that have TTX. My research has focused on further investigating three topics with this research: production, predation, and identification of novel TTX bearing taxa. In order to perform this research I first refined a Competitive Inhibition Enzymatic Immunoassay methodology to quantify levels of TTX in …

Using Qual2kw As A Decision Support Tool: Considerations For Data Collection, Calibration, And Numeric Nutrient Criteria, Andrew J. Hobson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface water quality in the United States is managed by the U.S. Environmental Protection Agency (EPA) under direction of the Clean Water Act. Designated uses are required for all state waters. Numeric or narrative water quality standards provide measures to determine if each waterbody meets the intended use. Narrative standards typically include vague terminology that is difficult to interpret and this has led EPA to encourage states to develop numeric criteria for nutrients in all its streams, rivers, and lakes. These numeric nutrient criteria are intended to stave off the harmful effects of over-growth of aquatic plants which can result …

Forest Recovery, Nutrient Cycling And Carbon Sequestration In A Southern Appalachian Spruce-Fir Forest, Patrick T. Moore

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Our forests provide us with a variety of services from clean water, forest products and wildlife habitat to the lesser known functions of nutrient cycling and carbon
sequestration. This research helps to demonstrate the extent of some of these services in a heavily disturbed southern Appalachian spruce-fir forest within Great Smoky Mountain National Park, the most heavily visited National Park in the United States. Following a catastrophic infestation of the non-native balsam wooly adelgid, the future of this forest was unknown, causing some to speculate about the future of this sensitive forest type. Though predictions about this forest’s future varied …

Integrated Management Of Downy Brome (Bromus Tectorum L.) Infested Rangeland, Heather Elwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Invasive weed species are a threat to the health and functionality of many rangeland systems. Downy brome (Bromus tectorum) is an invasive annual grass that affects the productivity of rangelands by decreasing the grazing capacity for livestock as well as altering the wildfire cycle and competing against more desirable vegetation for limited resources.

In 2006, an Invasive Plant Management Plan and Environmental Assessment was approved for Dinosaur National Monument, calling for prioritization of invasive species management on high value wildlife habitat, vector areas, and for species with a high ecological impact. The Cub Creek Watershed was identified as a priority …

An Environmental History Of The Bear River Range, 1860-1910, Bradley Paul Hansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study of environmental history suggests that nature and culture change all the time, but that the rate and scale of such change can vary enormously. During the late 19th and early 20th centuries, Anglo settlement in the American West transformed landscapes and ecologies, creating new and complex environmental problems. This transformation was particularly impressive in Cache Valley, Utah's Bear River Range. From 1860 to 1910, Mormon settlers overused or misused the Bear River Range's lumber, grazing forage, wild game, and water resources and introduced invasive plant and animal species throughout the area.

By the turn of the 20th century, …

A Data-Intensive Assessment Of The Species Abundance Distribution, Elita Baldridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

One of the most commonly observed patterns in ecology is the fact that at most locations there are a large number of relatively rare species, composed of only a few individuals per species, and a small number of relatively common species. This pattern of commonness and rarity is quantified by the species abundance distribution. As one of the most commonly observed patterns in ecology, it has been studied intensively for over 100 years.

A major emphasis of this research has been developing models to try to understand the forces that generate such a general pattern. As a result, there are …

The Effects Of Bison On Cattle Winter Range In The Henry Mountains Of South Central Utah: Resolving A Conflict, Ian M. Ware

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American Bison in the Henry Mountains are one of the last free-roaming, genetically pure herds of bison remaining in North America. Over the last decade, the herd has used a cattle winter range during the summer and early fall, creating a conflict between the wildlife officials who manage the bison population, and Bureau of Land Management officials and local ranchers who manage the rangeland. At the heart of this conflict is the question of whether bison are negatively impacting the rangeland resource, potentially reducing the abundance of preferable plant species. Negative impacts could include reduced forage availability in the …

Spider Community Composition And Structure In A Shrub-Steppe Ecosystem: The Effects Of Prey Availability And Shrub Architecture, Lori R. Spears

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Habitat structure is cited as an important factor influencing organisms, but few studies investigate whether habitat structure interacts with other environmental variables to affect community dynamics. The purpose of this study was to determine, using field experiments, the importance of prey availability and shrub architecture on a spider community in northern Utah, USA. We were also interested in determining whether surrounding shrub architectures influence spider and prey responses.

Our results suggest that spider distribution, abundance, and biodiversity are influenced by shrub architecture. Shrub architecture influenced spiders both directly and indirectly via associated changes in prey availability. Spiders were also directly …

A Multi-Phase, Mixed-Method Regional Analysis Of Lake And Reservoir Based Recreational Opportunities In Utah, William S. Spain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managing and planning for human use at lakes and reservoirs creates challenges for land and water management agencies in Utah and the country as a whole. In spite of increased attention and research, management problems such as conflicts, accidents, and site impacts continue to occur. These problems have been exasperated by an 800% increase in the number of registered boats statewide over the past 50 years. As such, developing new strategies to address the broad array of management challenges could be beneficial to the recreation management of lakes and reservoirs. This study, conducted in collaboration with Utah State Parks, considers …

The Influence Of Geology And Other Environmental Factors On Stream Water Chemistry And Benthic Invertebrate Assemblages, John R. Olson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Determining if a stream has been degraded by human activities requires knowing what that stream’s natural water quality and freshwater species composition would likely be without any alteration. However stream natural conditions vary greatly from stream to stream, making predicting natural conditions difficult. To determine natural stream conditions, I developed models to predict natural stream water chemistry at individual streams across the western USA. Specifically, the models predict a stream’s electrical conductivity (a measure of the amount of solids dissolved in water), acid neutralization capacity, and concentrations of calcium, magnesium, sulfate, total phosphorus, and total nitrogen. These models predict chemistry …

Effects Of Cache Valley Particulate Matter On Human Lung Cells, Todd L. Watterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During the wintertime, residents of the Cache Valley are very aware of the poor air quality that occurs during cold-air inversion episodes. If one somehow avoids the radio and television announcements as well as the electronic roadside signs indicating poor air quality and encouraging less driving, one need only to look upward toward the mountains that surround the valley and notice the lack of daytime visibility. This lack of visibility and health warnings are due to particulate air pollution or particulate matter (PM). PM is only one of many types of regulated air pollution but is the one that occurs …

Potential Effects Of Altered Precipitation Regimes On Primary Production In Terrestrial Ecosystems, Joanna S. Hsu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In addition to causing an increase in mean temperatures, climate change is also altering precipitation regimes across the globe. General circulation models project both latitude-dependent changes in precipitation mean and increases in precipitation variability. These changes in water availability will impact terrestrial primary productivity, the fixation of carbon dioxide into organic matter by plants. In my thesis, I addressed the following three questions: 1.) What will be the relative effect of changes in the mean and standard deviation of annual precipitation on mean annual primary production? 2.) Which ecosystems will be the most sensitive to changes in precipitation? 3.) Will …

The Decline And Conservation Status Of North American Bumble Bees, Jonathan B. Koch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several reports of North American bumble bee (Bombus Latreille) decline have been documented across the continent, but no study has fully assessed the geographic scope of decline. In this study I discuss the importance of Natural History Collections (NHC) in estimating historic bumble bee distributions and abundances, as well as in informing current surveys. To estimate changes in distribution and relative abundance I compare historic data assembled from a >73,000 specimen database with a contemporary 3-year survey of North American bumble bees across 382 locations in the contiguous U.S.A. Based on my results, four historically abundant bumble bees, B. …

The Effect Of Stream Restoration On Preferred Cutthroat Trout Habitat In The Strawberry River, Utah, Nicolas R. Braithwaite

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stream restoration has become a popular management tool for attempting to increase and/or restore fish populations by improving habitat. A section of the Strawberry River, Utah recently underwent a stream restoration project, where the main goals of the project included increasing spawning activity, rearing potential, and resident populations of Bear Lake cutthroat trout Oncorhynchus clarkia utah. The impact of the restoration project on cutthroat trout was investigated by first characterizing preferred habitat for different life stages, investigating habitat as a limiting factor in the system, and then assessing the quality of available habitat by comparing restored/unrestored sections of stream …

Establishing Weed Prevention Areas And Evaluating Their Impact, Stephanie Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spread of invasive weeds continues to be a serious economic and environmental threat. Weed prevention has the potential to stop weeds before they become well established in an area conserving time, energy, and resources. Unfortunately, weed prevention is often overlooked. Weed Prevention Areas (WPAs) are a relatively new tool developed to help improve the application of weed prevention. They are cooperatively managed areas that focus on implementing prevention and early detection strategies at a community level. The purpose of this research was to establish baseline data that will be used to evaluate the overall effectiveness of the WPA concept, …

Riparian Bird-Habitat Association Models: A Framework For Informing Management And Developing Restoration Guidelines In Utah, Hillary M. White

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Approximately 75% of the avian species in Utah use riparian habitats at some time during their life cycles and at least 80% of this habitat in Utah has been lost or altered since settlement; currently 0.6% of land cover in Utah is considered riparian. In 1992, with the support of Utah Partner's in Flight, the Utah Division of Wildlife Resources began a statewide neotropical migratory bird (NTMB) and habitat monitoring program to assess the status of bird populations at 31 sites. Additional sites (up to 52) were added in later years; bird and habitat assessments at 37 riparian sites have …

15n Tracer And Modeling Analyses Of Nutrient Transport Through Lakes In A Subalpine Watershed, David M. Epstein

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lakes have historically been overlooked as important nutrient processors within their watersheds. In general ecologists have focused on streams as zones of uptake and transformation, while viewing lakes as simple nutrient traps. However, recent research has highlighted the large influence that lakes may have on water chemistry within their watersheds. Within the field of limnology, researchers have traditionally focused on the pelagic zone for in-lake production. Further research in shallow lakes has highlighted the role benthic production within the littoral zone plays in the lake ecosystem. The greater influence of lakes is highlighted when comparing watersheds containing lakes with watersheds …

The Decline And Conservation Status Of North American Bumble Bees, Jonathan Berenguer Koch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several reports of North American bumble bee (Bombus Latreille) decline have been documented across the continent, but no study has fully assessed the geographic scope of decline. In this study I discuss the importance of Natural History Collections (NHC) in estimating historic bumble bee distributions and abundances, as well as in informing current surveys. To estimate changes in distribution and relative abundance I compare historic data assembled from a >73,000 specimen database with a contemporary 3-year survey of North American bumble bees across 382 locations in the contiguous U.S.A. Based on my results, four historically abundant bumble bees, B. …